Machine for cutting sheets



Dec. 2, 1941. 3 DE CRQCE 2,265,028

MACHINE FOR CUTTING SHEETS Filed Aug. 2, 1940 1 Z I 26 r: I 1: I II i:

58% J; I J16 22 20 A9 i WITNESSES: INVENTOR v fiewrrera fleCroce;

ATTORN I- IY Patented Dec. 2, 1941 MACHINE FOB CUTTING SHEETS Gennero Dc Croce, Kenmore, N. Y., assignor to Westinghouse Electrics; Manufact Company, East Pittsburgh, Pa., a corpora ion of Pennsylvania v Application August 2, 1940, Serial No. 349,788

1 Claim.

My invention relates to control systems for sheet cutting machines, and more particularly to systems of control for cutting glass, or other plastic material.

Heretofore in the cutting of glass, plastic glass is fed vertically through sizing rolls vertically into a cutting machine. This machine has a frame tact members l1, field winding l8 to the negative and a limiting bar or stop. when the limiting bar is moved to its limit, the glass feeding is stopped and a scoring tool is manually moved over the face of the glass to score it. The attendant bumps the sheet to break it on the score line and then removes it manually to a platform or conveyor. The cycle is then repeated.

One object of my invention is to make all the operations automatic to eliminate the time, labor, and cost of producing glass plates or sheet, or plates or sheets of similar material, as stiff rubber, plyboard, paper, or the various plastics.

Another object of my invention is to increase the efiiciency of producing glass sheets.

Other objects of my invention will become more apparent from a study of the following specification and the accompanying drawing, in which:

Figure 1 is a front view of a glass cutting machine, shown somewhat schematically;

Fig. 2 is a side view of the showing in Fig. 1;

Fig. 3 is a diagrammatic showing of the electric control for the glass cutter motor; and

Fig, 4 is a diagrammatic showing of the electric contrci for the glass remover motor.

The understanding of my invention may I be had from a study of a typical operating sequence or cycle of operation. Assuming the various buses, indicated by the plus and minus signs are energized, then an energizing circuit is established through conductor I (Fig. 3) through glass-movement limit'switch 2, actuating coil 3 of control relay 5 to the negatively energized conductor 4.

Operation of control relay 5 causes the closing of contact members 9 and opening of contact members 29 and 38. Opening of contact members 29 and 38 prevents energization of the control relay 3'! and the forward directional contactor 3| so that no false operation may be obtained. Closing of contact members 9 establishes a circuit from conductor I, through conductor 8, contact members 9, limit switch l0, actuating coil ll of. reverse directional contactor l2, to conductor I 3.

Operation of reverse directional contactor l2 line.

Themotor M, coupled to shaft I8 (see Figs. 1 and 2), thus drives the threaded member 20 through-reduction gear 2|. The nut 22 mounted on the member 20 and restrained from rotation by the cutter guides 23 thus moves the cutter 24, coupled to the nut 22, to the start position, which, as shown in Fig. 1, is the left-hand position.

When the cutter or nut is in the start position, it actuates the limit switch ID. This operation thus opens the circuit for coil II, and the cutter is thus stopped in the start position.

The glass rolling and sizing machine (not shown) now moves a sheet of glass into the cage 25, and as it moves up it engages vertically slidable middle cross-member 25 which in turn moves up and operates limit switch 2 toopen it. Opening of limit switch 2 deenergizes control relay 5 and in consequence contact members 29 and 38 are closed. Opening of limit switch 2 also stops feeding of the glass to frame 25 by suitable means old in the art.

Closure of contact member 38 does not yet close a circuit at this stage, but the closure of contact member 28 establishes a circuit from conductor 21, through contact members 28 and 29, actuating coil 30 of forward directional contactor 31 to conductor l3. Operation of forward directional contactor 3| now establishes a circuit for motor M, which circuit may be traced from conductor l4 through contact members 32, armature 16, contact members 33 and field winding l8 to the negative line.

The motor thus operates in the forward direction, thus operating the cutter transverse of the sheet of glass, that is, to the right in Fig. 1, and scores the glass sheet. The cutter may either cut the glass all the way through, or preferably mere- 1y score it. When the cutter arrives at the extreme right, it actuates the bumper bar 34 by means of a cam, or bell crank lever, or other means (not shown) coacting with nut 22. The bumper bar strikes the glass and breaks it on the line of the score, so that the sheet is ready for removal. The nut 22 also actuates the limit switches 35 and ll to close them.

Closure of limit switch 35 energizes coil 36 of control relay 31, and this relay holds itself in closes the contact members l5 and I! to enerthrough contact members 38 and 39. By the 4|, already mentioned, -a circuit is established for control relay 44, and this relay holds itself in cycle may .now repeat itself as soon as bar 25 again opens limit switch.

From the foregoing, it is apparent that I have provided a very efllcient control for a glass cutting machine or a machine cutting similar plasthrough limit switch 42 and contact members 43.

Operation of control relay 44 also closes contact members 45, thus causing operation of the forward directional contactor 46, and also causes opening of the contact members 4? to prevent operation of control relay 48 and thus'the operation of the reverse directional contactor 59.

Operation of the forward directional contactor 46 establishes a circuit for glass removing motor M, which circuit may be traced from line 50 through contact members 5|, armature 52, contact members 53, field 54 to the negative line.

The motor M thus, through pinion 56 and sector 51, operates frame 55 clockwise to lay the glass sheet on the conveyor belt or platform 58.

As the glass is removed, limit switches 2 and,

59 are closed. Closure of limit switch 2 merely again starts movement of glass into cage 25 and also effects shunting of contact members 40 through operation of relay 5, so as to make the return movement of the cutter for the time being independent of control relay 3]. In other words, if the cutter is not yet in the start position, it will continue to move to that position regardless of control relay 31 until limit switch I0 is opened.

Closure of limit switch 59 does nothing until limit switch 42 is opened. Limit switch 42, however, opens when the glass is on the conveyor, and since limit switch 4| is already open, control relay 44 is'deenergized, closing contact members 41 to thus actuate relay 48 to close contact members 50. Closure of contact members 60 actu ates reverse directional contactor 49.

Operation of reverse directional contactor cstic materiah- The production is thus very materially increased, and time, labor and money are saved. Further, voltage failure sets the circuits 'so that the cutter is returned to the start position upon return of voltage.

I am, of course, aware that others, particularly after having had the benefit of my teachings may devise other circuit diagrams for accomplishing the same or similar novel results, I, therefore, do not wish to be limited to the particular system of control shown and described, but wish to be limited only by the scope oi the claim hereto appended.

I claim as my invention:

In a machine for producing sheets of fairly rigid material, in combination, a cage, means for moving sheet material into the cage, an electric motor, a cutter connected to be operated by the motor, means responsive to the movement of a given length of sheet material into the cage to stop the means for moving the sheet material into the cage and for initiating the operation of the motor operating the cutter to thus cut a given length of sheet material, a second electric motor, sheet removing means connected to be operated by the second motor, and means, responsive to the completion of the cutting of the sheet, for causing the operation of the said second motor, and means, responsive to the completion of the removal of the sheet from the cage, for starting the means for moving the sheet material into the cage.

GENNERO DE CROCE. 

